What is the point of having a different skill for Persuasion and Deception? [closed]

Question

2 skills related to Charisma are Deception and Persuasion. A character could be proficient in any of the two. I know that a Cha (deception) check is made when a character attempts to convince someone else of a lie, while a Cha (Persuasion) check is made when arguments are used to convince someone of something.

To me the important distinction was always: is the arguments you are making based on a truth or a lie?

• Trying to convince a guard that the king is in danger (a truth) and you need to get in the castle, with the intention of saving him? Persuasion.
• Trying to convince a guard that the king is in danger (a lie) and you need to get in the castle, with the intention of stealing from the treasures? Deception.

But in the end, you're still just trying to convince someone. The arguments that you use would be the same whether or not you are lying about them.

I've seen people say that Cha (deception) checks involve arguments that are harder to defend/prove. Yet a case where the party is ambushed by ghosts, in the middle of the city, would have a better chance convincing the guards that come asking about the commotion that it was simply a few drunks (Deception), than ghosts (Persuasion).

Why then is there a need for 2 different skills?

To be clear, it does not matter what the designers intended (nor can we answer that for sure). This question is about: what is the real difference between the two skills and why is it important to have the two skills instead of a single one?

Answer 1

Well, a "why" question can be tricky if you're asking about why the designers chose to do things that way, as unless you can get a quote from them on the process and reasoning they used we're just speculating.

What's does the book say?

But, presumably the designers thought it was somewhat clear enough to make them separate skills. So, let's take a look at the differences between Deception and Persuasion, and see if we can draw as clear a line as we can between them. Quoting from the online Basic Rules, "Using Ability Scores", "Using Each Ability", under "Charisma Checks":

Deception. Your Charisma (Deception) check determines whether you can convincingly hide the truth, either verbally or through your actions. This deception can encompass everything from misleading others through ambiguity to telling outright lies. Typical situations include trying to fast-talk a guard, con a merchant, earn money through gambling, pass yourself off in a disguise, dull someone’s suspicions with false assurances, or maintain a straight face while telling a blatant lie.

Persuasion. When you attempt to influence someone or a group of people with tact, social graces, or good nature, the DM might ask you to make a Charisma (Persuasion) check. Typically, you use persuasion when acting in good faith, to foster friendships, make cordial requests, or exhibit proper etiquette. Examples of persuading others include convincing a chamberlain to let your party see the king, negotiating peace between warring tribes, or inspiring a crowd of townsfolk.

For Deception, phrases that stick out to me are "hide the truth", "mislead others through ambiguity", "pass yourself off in a disguise", and "maintain a straight face".

For Persuasion, phrases that stick out to me are "tact", "good nature", "foster friendships", "proper etiquette", and "inspiring a crowd".

So how do I tell which one to use?

Sure, I can see that there could be some overlap in some cases and can certainly understand your concern. But I think the key is to focus on what you're doing and the skills you'd need to do them, not solely just on what you're saying or whether what you're trying to convince somebody of is the truth.

Are you trying to invent a plausible reason for the guard to let you in? Sounds like Deception.
Are you trying to put the guard at ease for the guard to be able to trust you? Sounds like Persuasion.
Are you trying to disguise yourself as another guard or as a noble? Sounds like Deception.
Are you trying to have the guard have a stronger sense of duty to the king? Sounds like Persuasion.

Any of those actions could be taken in an encounter with a guard, regardless of whether the reason you're trying to talk to the guard is entirely truthful. And an encounter with the guard could quite reasonably involve multiple actions and therefore multiple checks, as you need to find which guard seems most friendly or distracted (Wisdom/Insight), make friends with him (Persuasion), and come up with a plausible reason for the guard to let you in (Deception). Each interaction that could have interesting consequences for the story (based on whether it succeeds or fails) could have its own check, and those checks should help you tell your overall story.

I'm getting a little sidetracked, but for more information on how social encounters can have multiple checks and be more interesting than saying "I throw a Deception at the guard" instead of "I throw a Dagger at the guard", see How to challenge a pacifist party as well as The Angry GM's Systemic InterACTION.

What if either Deception or Persuasion could work?

Even after all that, it's quite possible that a player could take an action where the DM is really unsure which skill proficiency should apply, or it seems that either could apply equally well. In that case, the DM could reasonably just allow the player to apply their proficiency if they have it in either. Remember, there are no skill checks, just ability checks. From the general Ability Check rules (with my emphasis added),

For every ability check, the DM decides which of the six abilities is relevant to the task at hand and the difficulty of the task, represented by a Difficulty Class.

…

Sometimes, the DM might ask for an ability check using a specific skill—for example, “Make a Wisdom (Perception) check.” At other times, a player might ask the DM if proficiency in a particular skill applies to a check. In either case, proficiency in a skill means an individual can add his or her proficiency bonus to ability checks that involve that skill. Without proficiency in the skill, the individual makes a normal ability check.

So, when a player takes an action interacting with the guard, the DM can just call for a Charisma check, and the player can (and should) say "Does my Persuasion proficiency apply?", and the DM can make a reasonable ruling on that question by itself, even if he'd answer the same way if asked "Does my Deception proficiency apply?". And certainly the DM could shortcut this, and just say "Roll a Charisma check, and you can apply either Deception or Persuasion". This can be part of a general "When in doubt, rule in favor of the players" approach that many DMs already have.

Answer 2

Because they both require different things to be great at them

So the other answers seem to be answering more "When would you use deception versus perception?" but that does not seem to be your question.

Here are the descriptions of the relevant skills:

Deception. Your Charisma (Deception) check determines whether you can convincingly hide the truth, either verbally or through your actions. This deception can encompass everything from misleading others through ambiguity to telling outright lies. Typical situations include trying to fast-talk a guard, con a merchant, earn money through gambling, pass yourself off in a disguise, dull someone’s suspicions with false assurances, or maintain a straight face while telling a blatant lie.

Persuasion. When you attempt to influence someone or a group of people with tact, social graces, or good nature, the DM might ask you to make a Charisma (Persuasion) check. Typically, you use persuasion when acting in good faith, to foster friendships, make cordial requests, or exhibit proper etiquette. Examples of persuading others include convincing a chamberlain to let your party see the king, negotiating peace between warring tribes, or inspiring a crowd of townsfolk.

Different Skill Sets

The answer lies in the fact that, persuasion and deception are inherently different skill sets (though often used together in real life).

Being persuasive (in game terms) means that you can be friendly, approachable, polite. You are good at following etiquette and making mediations. These things all come from an area of good faith. Being good at persuasion means being able to speak well, fit in, make friends, etc.

Deception is all about subterfuge and lies. Everything about deception is false and requires a separate set of skills to do it well. When you tell lies you have to keep your body in check (don't blush or look flustered or nervously fidget), you have to come up with a good lie (which means being able to think of a good lie to start with, keeping your story straight for as long as you need to keep it going, remembering who you told what, have a good memory for details, etc.) you have to be possibly comfortable using stealth and disguises (moving around in disguises convincingly, coming up with and remembering fake identities). so, you can see that while there might be some overlap, deception is going to need a separate set of skills.

Real Life Examples

I've known many people that would qualify as persuasive, but some of them were AWFUL liars. When it came to giving a good rousing heartfelt speech they were absolutely amazing. But ask them why they blew you off last night and they'd mutter and get all flustered or come up with a crappy story or mess up the details of the story such that it is an obvious lie.

I've also known the opposite. People that tell a LOT of lies and are very good at it. So they would be the ones that could stare a teacher right in the face and tell them a new excuse every day about why they didn't have their homework, and they'd be believable. But ask them to make a product pitch or rousing speech or to make friends was a difficult task.

There is obviously some overlap, some persuasive people are very good at lying (politicians, used car salespeople, etc.). And they are related, but the game does simulate that as well since both skills rely on charisma. This means that a charismatic person will have a lot of the base skills necessary to be good at either or both of these things, but to be great at either you have to fine tune those specific and differing skill sets.

So, simply, the reason that they are separate in game is that not only do they have different uses, but they have different skills and abilities required to be good at each of them.

Answer 3

Deception is to hide something, Persuasion is to show something.

If the guard by default lets everyone go inside the castle you don't need to show your honesty, just to hide your dark motives, so it will be Deception (unless you don't have any dark motive, so there is no need for a roll).

If the guard is super-suspicious and doesn't let anyone enter you will have to grab his attention and make him believe you when he could just ditch you away: it is Persuasion.

If you want to convince the lazy guards that they should do something about the ghost issue: Persuasion.

If the guards are asking for explanations about you walking in the streets with unsheathed swords: Deception.

There is no competence associated with proving that you are honest when telling the truth.

Answer 4

Different classes and backgrounds can only choose either Persuasion or Deception as a starting skill.

Clerics, paladins, guild artisans and nobles can only chose Persuasion; warlocks, criminals and charlatans can only choose Deception.

This ultimately goes back to earlier editions of D&D, where those skills worked very differently from each other. In 3rd edition. Diplomacy modified NPC Attitude, which required a fixed DC to make a character more helpful, while Bluff was an opposed check against the opponent's Sense Motive to convince them of a specific fact, which could also be used to feint in combat. As in 5th edition, certain classes had access to one but not the other.

The Ability Check Proficiency variant in the 5th edition Dungeon Master's Guide allows you to bypass the issue by giving each character proficiency in all checks using two ability scores (one from class, one from background). Under this variant, a character proficient in Charisma applies it to both Persuasion and Deception.

Answer 5

The main difference is that when you're lying you're inventing information, you need to make sure that all of the things you fabricate don't contradict anything you've already said or know of, you also need to concentrate on seeming sincere on top of this.

Answer 6

A lie is when you make a statement that you believe is false. Deception is the skill of telling a lie and making someone believe that you actually believe the statement is true. Failing at deception is when someone realizes you are lying.

An argument is when you state an opinion and provide reasons for someone to agree with it. Persuasion is the skill of making an argument and getting someone to agree with it. Failing at persuasion is when someone disagrees with your opinion despite your reasons.

The key difference is that with persuasion, you want someone to agree with something; with deception, you want someone to believe that you believe something.

Answer 7

Comparing Deception and Persuasion with Stats other than Charisma

The DM may rule that a different stat applies to a check you are trying to make:

In some situations, though, your proficiency might reasonably apply to a different kind of check. In such cases, the DM might ask for a check using an unusual combination of ability and skill, or you might ask your DM if you can apply a proficiency to a different check. PHB p175

Applying a different stat to a social check can show how Deception and Persuasion can be used differently, rather than just trying to come across as convincing and likeable (Charisma).

Perhaps your wizard is trying to out-debate his rival in the guildhall before an audience of the archmages?

...An Intelligence (Persuasion) check could be used to win the debate by making a reasoned, logical argument that everyone present can follow and your rival struggles to rebut.

...An Intelligence (Deception) check could be used to win the debate by weaving mind games and dishonest tactics into your argument that discredits your rival and your audience don't pick up on.

Answer 8

In asking "Why are there two skills?" you could be asking why two skills are necessary or why one skill isn't sufficient (within the context of the game). Most of the other answers deal with the first interpretation, but by raising the plausible scenario of a truth being less plausible than a lie, you've invoked the second as well. In that context, the answer is:

In 5th Ed, they probably shouldn't be.

One of the main philosophies in the skill simplification from 4E carried over into 5E is that skills should represent reasonably broad and intuitively linked proficiencies, as Keith Baker elucidates in his blog. This is why 3.x's Hide and Move Silently were combined into a singular Stealth skill. It isn't that some (real-world) people aren't bad at one but good at the other -- as this forum discussion explores, there are plenty of obvious cases in which it makes sense to use one but not the other. The problem is that for a D&D character, it far more often makes sense to be proficient in both rather than just one.

D&D is full of such examples, which are sometimes distinguished in other systems -- like 7th's Sea's Roll-Keep system, which distinguishes between the martial skills needed to operate different weapon group types. In reality, there's no particular reason why someone who learns to use a bow in their early development but uses a longsword regularly would progress in their bowmanship at about the same rate they progress in their swordsmanship. It's merely a convenient dramatic assumption for D&D, which helps keep the focus on tactical choices.